Glaucoma is an intractable ocular disease with a risk of blindness, involving an increase in intraocular pressure due to various predisposing factors and the disorder of internal tissues of eyeballs (retina, an optic nerve, and the like). A general method of treating glaucoma is intraocular pressure lowering therapy, which is exemplified by pharmacotherapy, laser therapy, surgical therapy, and the like.
In the pharmacotherapy, a drug such as a sympathomimetic drug (a nonselective stimulant such as dipivefrin or an α2-receptor agonist such as brimonidine), a sympatholytic drug (a β-receptor antagonist such as timolol, befunolol, carteolol, nipradilol, betaxolol, levobunolol or metipranolol, or an α1-receptor antagonist such as bunazosin hydrochloride), a parasympathomimetic drug (such as pilocarpine), a carbonic anhydrase inhibitor (such as acetazolamide), a prostaglandin (such as isopropyl unoprostone, latanoprost, travoprost or bimatoprost) is used. Further, Rho-kinase inhibitors (such as SNJ-1656), adenosine agonists (such as INO-8875), serotonin antagonists (BVT-28949), and the like have been under development as novel drugs. Other than these, a prostaglandin E2 receptor subtype 2 agonist (EP2 agonist) is known to have an intraocular pressure lowering effect, and it is reported in WO 2010/113957 that a sulfonamide compound having high EP2 receptor selectivity and a potent EP2 agonistic activity is promising as a therapeutic drug for glaucoma.
There are several reports of the combined use of drugs having an intraocular pressure lowering effect to treat glaucoma. For example, Japanese Patent No. 2726672 reports the combined administration of a sympatholytic drug with a prostaglandin. WO 2002/38158 discloses a method of treating glaucoma by the combined administration of several drugs having an intraocular pressure lowering effect to eyes. WO 2004/019951 reports the combined administration of a Rho-kinase inhibitor with a prostaglandin, and WO 2004/045644 reports the combined administration of a Rho-kinase inhibitor with a β-receptor antagonist.
However, there have been no reports specifically disclosing a combination of isopropyl (6-{[4-(pyrazol-1-yl)benzyl](pyridin-3-ylsulfonyl)aminomethyl}pyridin-2-ylamino)acetate, which has a high EP2 receptor selectivity and a potent EP2 agonistic activity, with other preventive or therapeutic drug for glaucoma or ocular hypertension, and naturally, it has not been known at all as to what effect of such a combination is exerted on the intraocular pressure.